Saturday, January 31, 2009

I recently found out that my friend Trevor Herriot will have his latest book Grass, Sky, Song: Promise and Peril in the World of Grassland Birdspublished this month. I am really looking forward to reading it. Trevor came to visit a few years ago and we toured around the prairie of Valley County looking at the landscapes and talking about birds as part of a radio program, Pastures Unsung, that Trevor was working on then. I believe that this book is an outgrowth of that program. Trevor also recently started his own blog and you can find it on my sidebar. I found out about Trevor's new blog through Craig Larson at Native Shores who contacted me about some of my photos. Trevor had both of us listed on his sidebar and Craig wandered over to Prairie Ice. I have added Native Shores to my sidebar as well and I am looking forward to reading more about Manitoba from him (and I thought the winter has been cold and nasty here!).I also recently added Saskatchewan Birds, Nature and Scenery by Nick Saunders in Saskatoon as well. I have been following his blog for a while and finally realized I hadn't linked to it and so I got that fixed.

Thursday, January 29, 2009

Here are a few photos of the mountains along the Antarctic Peninsula. They were particularly snow covered this year. There really isn't much else I can say about this landscape. I think the photos hit the thousand word mark and then some.

Wednesday, January 28, 2009

There are two new book coming out soon that I am interested in seeing. The first is the Field Guide to Songbirds of South America: The Passerines by Robert Ridgley and Guy Tudor. This field guide isn't really new - I suspect it is a reworking of the duos previous two, rather large volumes - The Passerines of South America - Volume 1, the oscine passerines and Volume 2, the suboscine passerines. Even though it is not really new, the field guide format is much needed and appreciated. I remember birding in Argentina with a substandard guide and being very frustrated with the illustrations and information in that guide and wishing that I had even the plates from the Ridgley and Tudor books tucked into my pocket. I just wish they had finished the anticipated next volume(s) on the non-passerines of South America and had those plates and information to fit into the field guide as well. For now, I am still stuck carrying two field guides if I want to bird those countries of South America without their own decent field guide, such as Argentina. At least in southern Argentinal Alvaro Jaramillo, Peter Burke, and David Beadles Birds of Chile still serves as an excellent resource for all the birds found there.

The other new title I am looking forward to is a revison of the best field guide for birds, The Collins Bird Guide, which I previously reviewed here. Apparently there are a number of areas where this guide is being revised, including the gulls and raptors section. I haven't been able to find any news on when the revision is supposed to be released but one note I saw thought that it might be March of this year.

I just found a reference that suggests this title will be released early in June this year.

Saturday, January 24, 2009

"I now belong to a higher cult of favored mortals, for I have seen the albatross"..."Lying on the invisible currents of the breeze, the bird appeared merely to follow its pinkish bill at random." -Robert Cushman Murphy

I cannot have a post about albatrosses without at least one quote from Mr. Murphy. Actually I probably can't get through any post about seabirds without a quote from Murphy. He is a pioneer seabird biologist and the author of the classic, and one of my favorite books of all time, The Oceanic Birds of South America. I have a copy of this two volume set that was given to me by one of Montana's pioneering ornithologists, Clifford Davis and I treasure them for the wealth of information they contain as well as where they came from.Murphy explored South Georgia onboard the whaling brig "Daisy" which resulted in much of the material for the Oceanic Birds of South America, but also resulted in "Logbook for Grace" a wonderful account of the trip written from his diaries (Grace was his wife's name). More recently, Murphy's daughter Eleanor Mathews wrote Ambassasor to the Penguins, an expanded account of Murphy's South Georgia adventure complete with photos Murphy took while onboard the Daisy.

The most common albatross on any voyage to Antarctica is undoubtedly the Black-browed Albatross (Thalassarche melanophris). They are like the Pintado - they arrive behind the ship before we clear the Beagle Channel and stay with us throughout most of the trip. They are suberb aeronauts, as are all the albatross, and Murphy says "Every movement revealed the constant, delicate reactions of the mechanism of balance - the gentle, almost unnoticeable rocking and seesawing of the wings with the bird's body as a fulcrum, the gauging of the angle of the wings-axis with horizon according to the sharpness of a turn and their feat of "shortening sail" at a critical moment, the last capability being due to the structural advantage of jointed planes, which man has thus far been unable to build into his imitation aircraft."In the photo below you can see quite well the jointed planes Murphy described. The wings are so thin that when viewed head on, you can see quite well the joints projecting above the plane of the wing.

Below is an immature Black-browed Albatross.

The Gray-headed Albatross (Thalassarche chrysostoma) occurs throughout the range of the Black-browed Albatross but is much less common. They don't seem as interested in following the ship as the Black-browed either, often just showing up for a pass or two. I don't have many photos of this species and I had hoped to do better this trip. I managed to get a few photos, but I wish the light would have been better (it was overcast for most of our Drake Passage crossings, particularly when I was up and about).

Next is my favorite of the albatrosses. The Light-mantled Sooty Albatross (Phoebetria palpebrata). I once saw them described as "gentle beauty" and it resonated with me for this species. They (along with their close relative the Sooty Albatross) are the most aeronautic of all the albatrosses too. Again Murphy:"The long tail and long slender wings of Phoebetria are associated with a type of flight which also distinguishes the two species of this genus from all other albatrosses" and "During the morning four Sooty Albatrosses joined us and remained near-by for five hours, appearing to have no other purpose than to play in the howling wind for the admiration of us on board. Their ease and precision, and particularly their ability to vary their speed and to "stand still" in the air, put them in a class by themselves."

These two joined us in a snowstorm off of Adelaide Island.

And last, but certainly not least, is one of the big guys, the Southern Royal Albatross (Diomedia epomophoraepomophora). They, along with the Wandering Albatross (Diomedia elegans) have the largest wingspan of any living bird, nearly 3.5 m (11.5 feet). We didn't have many of these guys come close to the ship on this trip and so this was the only large albatross I got decent photos of. We did see a couple of Wandering Albatross too, but I don't have photos of those.

Wednesday, January 21, 2009

The beauty of these birds is not driven by spectacular plumage or dazzling colors, but the antithesis of gaudy and flashy. They are white. Pure, gentle white with jet black eyes and bill. Nothing else. They are pagophilic or ice loving birds and they are a quintessential Antarctic birds, highly associated with pack ice environments. I love when we get into ice and they start showing up, moving along the ice edge and then following the ships track through the ice, stopping to gather food items from the ice as it is turned over and tumbled in our tracks.

Typical Snow Petrel feeding habitat. They nest in small caves and cracks in exposed rocks throughout the Antarctic Peninsula.

This Snow Petrel caught a small fish, perhaps a Antarctic Silverfish (Pleurogramma antarcticum), a fish that is fairly common in seabird diets because unlike most other fish in Antarctica, these inhabit mid to surface waters. Like all other Antarctic fish, these lack a swim bladder. Most other species are found on the seafloor because they cannot float but the Silverfish maintain their boyancy through fat sacs in their body.

I have plenty more Snow Petrel photos and as I go through them I may post a few more.

Monday, January 19, 2009

During recap (short lectures and questions sessions usually centered around the day's activities) on one of the cruises I was on in December, someone asked how many feathers were on a penguin. I had no idea other than "lots." I knew that penguins had the highest feather density of all birds and were completely feathered without the feather tracts and apteria of other birds, but off the top of my head I had no idea what that density was nor how much surface area a penguin had.

I was doing some internet searches earlier today and thought I would look to see how many feathers were actually on a penguin. Turns out there wasn't anything I could find on Google or in my penguin books either. I did find some unreferenced numbers on feather density and some good numbers from research on the surface area of penguins from some heat loss/thermoregulation physiology studies. From those references I was able to determine that a Gentoo Penguin had a feathered surface area of 3288 square cm. and an Emperor Penguin has a surface area of 9000 square cm. I also found a number of references to feather densities ranging from 12 per square cm to 300! per square inch. I felt that the 12 per square cm figure was probably more accurate so I used that figure for both species and multiplied the numbers out to get approximately 36,700 feathers on a Gentoo Penguin and 108,000 feathers on an Emperor Penguin. I did find some information for the Little Blue Penguin that stated there were about 10,000 feathers on that species. That seems about right for the much smaller size of the Little Blue. My calculations may be a bit off since I am not sure where the feather density estimates came from on the penguin's body. There are many more smaller feathers on the head and flippers than on the torso of any penguin so I suspect my estimates may be a bit low but at least they are in the ballpark.

Saturday, January 17, 2009

Probably the most commonly observed bird throughout a trip to the Antarctic is the Cape Petrel (Daption capense). This species has been known by many names including Pintado, Speckled Haglet, and Damero. R. C. Murphy, in his classic "Oceanic Birds of South America" called them Cape Pigeons and had "small patience with the pedantry that would alter it to "Cape Petrel"".

They seem to delight in playing in the winds around the ship, often cruising within arms reach, hanging in the updraft on the windward side. They join the ship shortly after entering the open ocean and are a fixture at the stern until we return to the Straits of Magellan. Every year they are a welcoming committee for me, greeting me to the open ocean and a preview of upcoming sights to be seen further south.

They nest in cliff areas throughout the peninsula, tucked into cracks and crevices. These were on Deception Island.

Deception is a volcanic island where the cauldera has been breached by the ocean and the interior of the island forms a natural harbor. The interior of the island was once home to a shore based whaling station and the processing of whale carcasses provided a massive food source for many seabirds. Murphy also described the harbor at Deception as "often hidden under a raft of petrels of various sorts." He also notes that the pioneer Antarctic aviator Sir Hubert Wilkins described having to drive a power boat back and forth through the birds to clear a lane to allow the airplanes to take off and land.

The Antarctic Petrel (Thalassoica antarctica) is not as common and usually only found close to the continent in the vicinity of ice, often in the company of Cape Petrels. This year was good for observing Antarctic Petrels with large numbers found in early December north of King George Island. They are about the same size as the Cape Petrel but look as if the black and white checkered pattern of the Cape Petrel has been organized into pure brown and white sections.

The Southern Fulmar (Fulmarus glacialoides) seems to be much more local, particularly early in the breeding season. We didn't see many this year, but at one point there were a few that were feeding just off the stern of the ship amongst the zodiacs as we arranged a zodiac tour. They foraged with some Cape Petrels right up to the edge of the zodiacs as we were waiting to board the ship.

My favorite of the distinctive Antarctic petrels is the Snow Petrel. These however, deserve their own post so more photos to follow tomorrow.

Tuesday, January 13, 2009

I will always remember where I was on January 13, 2003. After nine months of waiting Laura and I greeted Benton James Carlson late in that night. He has grown amazingly fast and is a wonderful young boy. He knows his dinosaurs quite well, is learning how to read, and has lost his first tooth.

Prions are a group of rather small, speedy petrels found in the southern oceans. They are about the size of a Common Nighthawk and fly like bats - fast with lots of twists and turns as they dart over the waves - which makes them very difficult to identify and photograph . The various species all appear very, very similar. The most distinctive features of each species are the shape and size of their bills (see here for comparison of some species skulls where you can appreciate the differences in bill size and shape), a feature which is is unfortunately something hard to discern when you are standing on a pitching deck 20 feet above the water and the birds are rocketing past. Therefore honest identification is often limited to "prion species." Richard White, an excellent birder from the Lindblad Expedition staff with more Antarctic birding experience than anyone I know, most often list the prions on our trips as "prion sp." unless he gets diagnostic views or photos.

Identification guides make statements like "even with perfect views, identification to species may not be possible" (Onley and Scofield) or "even given current knowledge and and experience, some forms are usually unidentifiable at sea" (Shirihai). Shirihai presents the most honest view on prion identification. After describing a set of characteristics to distinguish the species he writes "At sea it is often very difficult to appreciate these differences, because of their subtlety and due to these species fast flight, poor sea conditions/visibility, and/or various lighting effects." After describing the Slender-billed Prion, one of the more distinctive species, he states "Bear in mind it is never easy to appreciate any of these characteristics, even if alongside other species at close range, and even for experienced observers." He also lists "other prions" when describing identification confusion risks for all the prion species.I feel that often people are deceived by the illusion presented in a number of identification guides that they can always identify birds to species when in fact for a number of very similar species it is often impossible to tell them apart. This pressure is probably most evident for birding guides, who are probably perceived by their clientele as not being a good guide or birder if they admit they are unable to make a specific identification, making the matter even worse and perpetuating the myth that these species are readily identifiable in the field.Digital photography has certainly helped with identification of prions for me and hopefully this tool will help others be more critical of their identifications (or help admit they just can't tell one from another with the views they have). A trip report I read recently illustrates this point. The report stated something like "the abundant Slender-billed Prions we observed during the day were later determined to be Antarctic Prions after further analysis of the photos taken during the day"There are eight species in the southern oceans, but thankfully for me trying to figure out which is which, only two, the Antarctic and the Slender-billed regularly occur in the Drake Passage.

Here are a few photos of what I have decided are most likely Antarctic Prions based on range (Drake Passage where the most likely candidates are Antarctic and Slender-billed), the tail configuration (dark central tail feathers with lighter out tail feathers, also narrowing the candidate species, helping confirm, but unfortunately not helping discern between the two already the most likely possibilities), bill shape and size (in the photos they look like they fit Antarctic better than Slender-billed because they appear larger and not as slender as they should for the latter but given my limited experience...), the contrast of the "m" markings on the back (more contrast suggesting Antarctic, the Slender-billed would have a much paler "M" mark), and abundance (Antarctic are the more common species in the area and are more prone to follow ships. This may be a self-fullfilling field mark but I will take it in this case).

I am still going through my prion photos to see if I can find one that looks more Slender-billed and Antarctic but as you can imagine, many (most) of the photos are going to be photos of a prion species, most likely Antarctic. Either way they it was certainly fun to watch these birds manouver through the fast changing thin zone between wind and waves.